Relationship Equations
by Cravenkun
Summary: Human!Perry/Heinz/Human!Peter In which Perry uses the distance, rate, and time formula to determine the intensity of Heinz's blushes and decides that three might be better than two. warnings: insubstantial fluff, angst, mentions of sex between a human!semi-aquatic mammal and evil scientist in a lab coat, author's first attempt at writing for the Perry/Heinz/Peter love triangle.


"Perry the Platypus?" Heinz asked hesitantly.

Perry rolled over so that he was facing Heinz, to show that he was listening to him.

"W-well, um," he hesitated and Perry began to suspect that it was something a bit more serious than the awkward aftermath Heinz usually displayed upon recovering himself from their activities. Yes, it definitely must be something unexpected, Perry decided, as Heinz repeatedly bunched and released the bed sheets in his hand. The other hand was holding his head above the pillow, supported by his elbow, with a face that looked much more pensive than the immensely pleasured one that he had shown Perry only moments before.

Perry propped himself up more properly, his face level with Heinz's only because of their position on Heinz's bed. He waited patiently until Heinz finally met his eyes and Perry held the other man's gaze. Heinz's eyes were the most expressive windows to the mind that Perry had ever encountered. He loved how they would shine when Heinz was on a roll with his latest scheme, or soften when speaking of Vanessa, or glow when Perry pulled away from a particularly breathtaking kiss that they shared.

Right now, those eyes told Perry of a story of countless experiences of saying the wrong thing and facing rejection. Perry could see it in the slight crease at the corners of his eyes, in the nervous flutter of eyelashes, and most of all, in the dark abyss of those wide pupils into which Perry could not follow, no matter how much he might wish to.

He didn't need to be told that Heinz was thinking of saying something that he thought Perry would not react well to. And while he understood Heinz's concern and knew that to him it was well-justified, Perry rather thought himself quite well-adjusted to dealing with such concerns. He hadn't trained as a secret agent, or had further (unintentional) training living with a family that had fairly outspoken individuals who might not always think before they spoke, in order to have everything he's worked toward lost at whatever Heinz was holding back from saying. Perry could handle it, whatever it was.

Perry reached out slowly, carefully (gently) and was rewarded when Heinz did not flinch but sighed as Perry's hand came to rest on the cheek opposite the one holding his head up. Perry managed to catch Heinz's eye again after a moment and allowed his own eyes to soften and his lips to form a half-smile that was the best he could manage when he had Heinz's explicit attention on him. He gently thumbed the corner of Heinz's mouth upward, trying to get him to do the same.

Heinz let out a nervous giggle and released the mangled bed sheets to lift his hand to cover Perry's own. Perry felt the other half of his mouth rise as well with his mission becoming accomplished as Heinz's lips turned up and his eyes lost their darker shadows.

"Ah, you're right Perry the Platypus, sorry... I just get so worried about some of these things, I mean we only just made our relationship official and all the other romantic relationships that I've had have all ended in disaster... And I really _really _don't want that to happen with you so-"

Perry used his conveniently placed hand on Heinz's face to place a hushing finger in front of his lips. He removed it only after Heinz appeared to understand Perry's intention.

"Right," Heinz took a deep breath and looked at Perry questioningly, seemingly asking for permission to continue. Perry nodded for him to go ahead but Heinz's look sparked a memory in Perry's mind; he had had a similar look on his face when he had asked Perry what he thought of-

"Okay, what I wanted to ask you, Perry the Platypus, is whether you've spoken with Peter the Panda recently," Heinz said, feeling surprisingly tense beneath Perry's hand for such a non-important subject matter.

-_Peter._

Perry blinked, surprised by the subject matter and Heinz's handling of it but not dismayed by it, as Heinz seemed to think he would be. He let his hand, freed from Heinz's which had dropped back to the rumpled bed-sheets, shift to Heinz's brow to skim questioningly along the furrowed skin as he shook his head.

_ 'No. Why are you worried?'_

Heinz swallowed and responded to the unvoiced question, "Because he was asking after you."

This was an unusually short answer from his normally quite verbose nemesis (_lover, _his subconscious reminded him with a thrill). The few other times that Perry could remember Heinz being so sparsely-worded was when Vanessa had been hit by a stray pipe that had burst from the leaky-faucet-inator and been knocked out cold, and after the first time he and Perry had had sex. And given that the last time Perry had checked he was always the first to know if anything bad had happened to Vanessa (_not _Peter the Panda) and having seen Vanessa whole and well not even 4 hours ago, Perry thought it safe to assume that whatever was on Heinz's mind at the moment was something to do with their relationship having just recently taken on a new physical level and Peter the Panda was somehow involved in that.

The logical conclusion then was that Peter had discovered the intimacy of his and Heinz's relationship, but Heinz's last statement didn't resonate with that line of thinking. _He was asking after you._ Why would Peter ask after Perry if he already knew the situation? The agent could have been meaning to ask Perry about a particular case of course, but Heinz's tone was all wrong for that. Besides, Perry wouldn't put it past Peter to hunt him down just to ask an inane question about an assignment whether Perry had been trying to make himself scarce at the agency or not.

So Perry looked to Heinz for answers.

Abruptly, Perry realized that he must have unknowingly been staring at Heinz during his internal questionings, for Heinz's face had become quite red and warm as it did when Perry stared at him for too long when they were in bed together (Perry had rather quickly worked out the equation for the rate of Heinz blushing: distance between him and Perry, divided by length of time spent making eye contact, minus amount of clothing left on their bodies). Quickly adjusting his gaze to a much softer look, Perry smoothed Heinz's brow with his thumb, sweeping his hand lower to cup the blood-warmed cheek with his cool palm.

Heinz's breathy, shaky laughter filled the space between them and the loud exhalation seemed to startle him into speech once more.

"S-sorry Perry the Platypus, it's just that you're hand is really cold and my face is really warm, ha ha..."

When Perry chittered in apology and made to remove his hand though, Heinz held it fast with one of his own and continued speaking once more.

"Oh! No, it's fine really, actually it feels quite nice you know, not bad at all, or should I say nICE, hee hee..."

Rolling his eyes, Perry most certainly did _not _smile but neither did he continue with releasing Heinz's face from his grasp. Which proved to be quite fortunate as Heinz abruptly brought his quirked lips to Perry's in a quick kiss and gosh Heinz's lips were certainly _warm _weren't they? and Perry suddenly found himself needing the stability that holding onto Heinz's face provided.

After pulling away with a final fleeting brush of lips on lips, Heinz's eyes were sparkling and he was damn near grinning and suddenly Perry was feeling very much like the shy one in this situation. Heinz squeezed Perry's hand before gently pulling it from his face and interlocking their fingers on the sheets, propping himself up to face Perry more fully. And as Perry watched Heinz open his mouth to explain why they were talking about Peter here, Perry couldn't tell which was more arousing: the fact that Heinz seemed to gain confidence from Perry's amusement at his ridiculous jokes, or that Heinz was able to comprehend and be reassured by the depth of Perry's infatuation with him. It would be embarrassing if Perry didn't know that it was so damn _good _for the insecure Heinz to be able to experience these things. In fact, the only other person that Perry could think of whom he believed could similarly boost Heinz's confidence was-

"Alright Perry the Platypus, I'll be honest, I'm a little nervous to be sharing this with you but I think it needs to be said so I'm going to say it anyway. So, I saw Peter the Panda a few days ago and he knows about us and he also knows how I feel about him and - Perry the Platypus, I don't know if you know this but Peter the Panda really does care for you even if he doesn't always act like it and of course he cares for me too but you already knew that and anyway what it is I'm trying to say is that Peter the Panda and I were talking about it and he seemed to think that we could work well together as a - as a triad of sorts and he wanted to know if you were willing to give it a chance?"

-Peter.

It shouldn't surprise Perry, not really anyway, knowing that this was Peter that they were talking about. The bastard always seemed to know what he wanted and made sure to let everyone else know too. Perry had to admit that there was a part of him that greatly admired that trait of the panda-like agent, having only just recently allowed himself to exhibit a similar quality.

Right now though, he was more focused on Heinz, who appeared to be wondering whether to wallow in regret at what he'd said out loud and promise himself never to speak aloud ever again (Perry highly doubted that would work out well) or if he should run away while he still had the chance (also unlikely to be very effective, considering the state of undress Heinz was in at the moment). Before Heinz had the chance to make do on either idea, Perry quickly brought his attention back to him with a quick squeeze to Heinz's hand.

The face that jerked back up to look at Perry had lost its brief burst of confidence from earlier and instead was filled with Heinz's signature closed off look that signaled his acceptance of what he considered was likely to be rejection forthcoming. This face was tinged with a faint yearning look that, had Perry had any doubt of Heinz's sincerity, would have immediately crushed any. As it was, Perry had no doubt of Heinz's stance on the matter (Heinz loved them both after all) and Perry also had no doubt that Peter would desire Heinz and be able to provide a loving relationship for the man; however, Perry didn't understand where he fit in there besides with Heinz - Peter had never shown any interest in him (really, if the hard stares Perry occasionally got from him were anything to go by, Peter certainly didn't like him much at all) besides as a source of personal amusement/usefulness and a connection to Heinz.

If Perry could doubt Peter's intentions towards him though, the one thing that he could have faith in was the panda-lookalike's best intentions at heart for Heinz and since Heinz cared for the both of them, then that good intention could pretty safely be expected to extend to include Perry as well.

Heinz, who was not privy to Perry's thoughts but who knew to allow Perry some space when he got the blank, airy look on his face that suggested he was thinking intensely, had been silent up to this point. But after several minutes of silence, his nature reasserted itself once more.

"So, Perry the Platypus...? I'll understand if you think it's too weird, I mean even _I _was a bit shocked when Peter the Panda brought it up, heh, can you imagine _me_, shocked? But I mean it wasn't necessarily a _bad _idea as long as you were okay with it, which of course you don't have to be okay with it, it's not like I would blame you, I mean you're certainly not obligated to be okay with any of this, since -"

Perry didn't actually hear most of what Heinz was saying as he was trying to smooth his expression into the formation that he wanted to show Heinz, and so judged by the speed and growing tinge of slight hysteria to the words when he'd best stop the man before he worked himself up too much. Another squeeze to the hand, accompanied by a reassuring thumb swipe, was enough to get Heinz's attention but it wasn't until their eyes reconnected and Heinz got a good look at Perry's face that he finally broke off from what he was saying.

Watching Heinz carefully, Perry was rather pleased to see that he seemed to be receiving Perry's message. For a person who always seemed to rely so heavily on dialogue to get his point across, Perry was always secretly proud of the fact that Heinz could pick up on so much Perry was trying to communicate, simply by facial expression. It had been a necessary skill to acquire for their relationship to flow as smoothly as it did (as it could anyway) but still, it wasn't everyone that could look at Perry's current expression and read the story he was telling in his features: forehead smooth, one eyebrow tilted slightly (open to possibilities) eyes round but not wide (accepting, trusting, not wary), nose flat (calm), mouth curving up, lips parted just slightly (affection, love, caring).

Heinz's slow, cautious smile was good, it meant that he was seeing what Perry was trying to tell him, but it wasn't enough. There was something more that Perry had to do, something else that he had to say that he couldn't just with his facial expression. So, Perry leaned forward, keeping his eyes open so that Heinz could see the warmth in them and gently bumped foreheads with him, teal hair mixing and meshing with brown hair, his lips pressing a warm (gratitude) kiss to the lips that had formed the words to sentences that were scary for the lips' owner to speak.

'_I'm proud of you.'_

And pride was important yes, especially for someone so unsure of themselves as Heinz but even more important, Perry felt, was for Heinz to know that he was loved.

Perry, still holding Heinz's warm gaze with his eyes, moved both his hands to lay on Heinz's person. His right he placed on the soft hair covering the skull housing the brilliant mind of this amazing person that was _Perry's _and the left he put over the rib cage protecting the pounding heart keeping the oxygen flowing through the precious person who made Perry's own heart beat fast. Perry placed his hands and looked with his eyes on the points that he felt encompassed the whole of Heinz Doofenshmirtz and felt the answering thrill run through him as Heinz looked wholly at him.

He didn't know how else to say _as long as I am with you I don't mind_ but Heinz seemed to hear him all the same.

A week later, Perry was wondering if he'd made a mistake. He had just walked in to Heinz's place (using the keys for once) when he was greeted by the sight of Peter sitting beside Heinz on the couch, planting kisses on Heinz's face as if they were going out of fashion. Not quite sure what to do with himself, Perry tried to edge past them (he _was _here looking for an inator after all) but Peter seemed to have developed super-human hearing since the last time Perry had seen him, as he glanced up at Perry with a smoldering stare that stopped the floundering agent in his tracks.

Perry had time to take in Peter's appearance before the other agent made another move and Perry had the distinct impression that Peter had meant for things to happen that way. Perry took in the sight of both Heinz and Peter's states of disarray (still clothed but looking as though that could really change at any moment), both men's faces tinged red (Heinz's far more so than Peter's), Heinz's dazed but immensely pleased look compared to Peter's sharply calculating gaze - a gaze that was currently trained on Perry in a familiar glare-off.

Peter suddenly smirked, his pale pink tongue flicking across his bottom lip, and Perry felt a jolt as he realized that it was not anger or hatred that sparked and burned in Peter's gaze when he stared at Perry, but _desire_. Peter's smirk only grew as he saw Perry's thought process flash across his face and Heinz, never one to be left unoccupied for too long, chose that moment to chime in, not bothering to adjust his clothing first.

"Ah, Perry the Platypus, what an unexpected surprise and by that I don't actually mean unexpected, of course, I had been hoping that you would actually show up. Peter did say that he wanted to show his gratitude to you for trying this out, you know. And that's not even getting into the fact that I have an evil scheme for you to thwart today."

Perry felt distinctly out of place with both of them staring at him, waiting, until Peter rolled his eyes, reached out, and dragged Perry onto the couch with them. With both men quite convincingly insisting that Perry stay with them (Peter was surprisingly adept at reading Perry, as the hand currently curled in and lightly pulling at his teal locks _just so_ attested to) it was rather easy for Perry to decide that the thwarting could wait. And as Peter settled himself at Perry's back, hands becoming possessively acquainted with the hair at Perry's nape and lips trying their best to do the same to the back of Perry's neck, and Perry picked up with Heinz where Peter had left off, making sure to spend extra time pressing kisses to the places Peter had not yet touched, and Heinz practically climbed in Perry's lap, Perry's trepidation began to diminish.

Maybe this could work out after all.


End file.
